Apparatus for photographic reproduction



March 16, 1965 J. G. B. HALDEN 3,173,351

APPARATUS FOR PHOTOGRAPHIC REPRODUCTION Filed Feb. 12, 1962 2Sheets-Sheet l In Our/or v6.5 Ger-ale! Erosion Mlle/61L March 16, 1965J. G. B. HALDEN APPARATUS FOR PHOTOGRAPHIC REPRODUCTION 2 Sheets-Sheet 2Filed Feb. 12 1962 [00:0 for d355, Gare Id Bro ctan //a )Jen W/ UnitedStates Patent 3,173,351 ARPARATUS ldtllll HQTUGRAPHEQ REl-RQDUQTEUNJoseph Gerald Brocton Hal-den, Loughton, England, assignor to @zalidCompany Limited, Loughton, England, a British company Filed Feb. 12,19-52, Ser. No. 175,866 6 Claims. (Cl. 95- 75) The invention relates tophotocopying apparatus and is especially concerned with apparatus forproducing diazotype prints from transparent or translucent graphicoriginals.

In one example of such apparatus a master consisting of a drawing or thelike on transparent or translucent material is brought into contact insuperposed relation with a sheet of diazotype or other sensitisedmaterial, and exposed to a source of actinic light by feeding the mastercopy and the sensitised material past the light source by means ofrollers, endless bands or belts or other conveying means.

Such machines are well-known and are theoretically capable of acomparatively high rate of output. In the feeding of sheets ofsensitised material and master copies to the machine it is, of course,necessary to ensure that when exposed to the source of light the two arein correct register.

it has been customary for such machines to be fed by hand and it hasthen been found in practice that the rate of feeding cannot becommensurate with the Working capacity of the machine; in fact it isquite usual for a machine to be fed in this manner at about onlyonefifth or one-sixth of its potential capacity. The machine is thusemployed wastefully, in that it is run at only a fraction of itspotential speed if operator efiiciency is to be maintained.

Diazotypc machines can be designed to run at speeds of well in excess of40 feet a minute, but survey has shown that even when a web ofsensitised material is used instead of separate sheets, once a speed ofabout 20 feet a minute is exceeded, hand feeding becomes inetlicient andconsequent unacceptable wastage of material results.

It is an object of the present invention to facilitate the employment ofphotographic, especially diazotype, reproduction apparatus up to itspotential capacity, in particular by enabling sensitised material to befed into the apparatus as a continuous Web or successive large sheetswhile eventually prints are delivered as cut sheets, the sensitisedmaterial and masters to be copied being meanwhile fed in a rate whichmay be commensurate with the potential capacity of the machine.

The invention comprehends machines which may be either wholly automaticor partly automatic and partly manually operated and capable of useeither with a continuous web or separate large sheets of sensitisedmaterial.

The present invention provides a photocopying apparatus comprisingmeans, at an exposure station, for exposing sensitised material, meansfor progressively feeding a web or succession of large sheets ofsensitised material to an assembly station, means at a cutting stationin the path of the sensitised material to the assembly station operativein response to control means each time a predetermined length of the webor of a large sheet has passed the cutting station, to cut the Web orsheet transversely thereby to produce a succession of sheets of apredetermined length, means at the assembly station Whereby the cutsheets and masters may be superposed on one another, and means forfeeding the superposed sheets and masters through the exposure station.

Particularly to enable hand-feeding of masters, means "ice may beprovided for temporarily arresting the cut sheets at the assemblystation.

There may he means for longitudinally slitting the Web or assets, beforeor after cutting transversely.

In one embodiment of the invention there is adjacent the assemblystation a detecting station having sensitised sheet detection means fordetecting the presence of a sensitised sheet at the detection station,master detection means for detecting the presence at the detectingstation or at another such station of a master to be copied, and meansresponsive to the detection of a sheet and of a master as aforesaid toassemble and feed the sheet and the master in superposrxl relationthrough the assembly station.

Preferably, in the embodiment just described the control means for thetransverse cutting means is located along the feed path at a distancealong the path from the cutting means equal to the length of sheetdesired, and is arranged to be responsive to the arrival at the controlmeans of the leading edge of the material to cause the actuation of saidcutting means.

The control means for the cutting means preferably operates, when theweb is cut, also to stop the feeding of the web to the cutting station.The feeding of the Web may be restarted when the presence of both amaster and a sheet is detected at the detecting station.

The sensing devices may comprise photoelectric cells which detect thepresence of the leading edge of the web.

Thus, if it is desired to sever the web at, say, 8" intervals aphotoelectric cell is located along the feed path at a distance of 8"from the guillotine blade, the photoelectric cell being so arranged thatas the leading edge of the material is sensed by it the guillotine isoperated transversely to sever an 8" length of web.

Subsequently, every time the leading edge of successive lengths ofmaterial is sensed by the photoelectric cell the guillotine is caused tooperate.

If desired, the location of the control means along the feed path may beadjustable to vary the length of the sheets cut from the Web.

Preferably the sheet detection means and the master detection means eachcomprise a photoelectric cell responsive to the presence of the leadingedge of a sheet and a master respectively.

It is further preferred that when the leading edge of only a master orof only a sheet is detected at the detecting station the detection meanswhich detects the master or the sheet operates to stop the feed of themaster or the sheet respectively.

In one machine according to the invention there is a plurality of masterdetection devices spaced apart across the path of the mastersrespectively and responsive to a plurality of masters advancing side byside.

Two embodiments of the invention will now be described with reference tothe accompanying drawings which illustrate more or less diagrammaticallytwo machines embodying the invention and in which:

FIGURE 1 is a sectional view of a machine which is partly automatic, andpartly handoperated, and which may be modified as described hereinafterto render it completely automatic.

FlGURES 2 and 3 illustrate control assembly whereby predeterminedlengths of sensitised material drawn from a roll are measured,

FIGURE 4 illustrates the disposition of slitting discs on a part of aslitting device, and

FIGURE 5 illustrates diagrammatically a sectional View of a secondmachine.

Referring now to the machine shown in FIGURES l to 4-, and first moreparticularly to FIGURE 1, three conveyor units 1, 2 and 3 are arrangedfor conveying the sensitised material from a roll 4 (of say 250 yds.) toa printing cylinder 5.

A roll locating device whereby the roll 4 can be positioned, comprises apair of arms 6 pivoted at "I" and carrying at their opposite ends halfbearings 8. The arms 6 are connected to double acting hydrauliccylinders 9, adapted in one position to raise the arms 6 andconsequently the half bearings 8 away from core shafts 16 carrying theroll 4, so that in this position of the arms 6 the roll 4 may be readilyplaced in position for actuation of the cylinders 9 to move the arms 6to their other position, in which the half bearings 8 are retained incontact with the said core shafts lltl. Locating rollers 11 adjustablymounted on the arms 6 serve to position the roll 4 correctly.

The roll 4 rests on and is driven by a main drive roller 12, ensuringthat the roll 4 is driven at constant linear speed notwithstandingvariations in diameter as the web material is fed from the roll 4.

As the web material is fed from the roll 4, the hydraulic cylinders 9thus ensure that the outer periphery of the roll is always maintained incontact with the drive roller 12.

The first conveyor unit 1 comprises two juxtaposed endless belts 13 and14, defining a feed path along which the sensitised material istraversed to the second conveyor unit 2. The endless belts l3 and 14pass around appropriately spaced guide rollers l5, 16, 17, 13, 19, 29,21, 22 and 23 at least one, preferably roller 19, of which is a drivenroller, moving the endless belts 13 and 14 in a direction to feed thesensitised material from the roll 4 to the conveyor unit 2 along thefeed path extending from rollers 21 and 22, roller .3, roller is androller 1?.

The length of the feed path in the example under consideration is 30inches, rollers 16, Ztl and 23 being adjustable to alter the effectivelength of the feed path (shown in dotted lines) to 32 inches thus toenable all different standard sizes of sheets to be accommodated.

Sensitised material drawn from the roll 4 passes through a nip formedbetween rollers 24 and 25, through a guillotine device generallydesignated 2% to the aforementioned feed path defined by belts l3 and14.

Rollers 24 and 25 serve as control rollers to measure the sensitisedmaterial as it is drawn from the roll 4, and are associated with wormdrive devices 27 and 28, from which drive is imparted to the electricallimit switches. To cater for correct feeding of different standard sizesof sheets, roller 2 is dimensioned to make one complete revolution forevery inches or" web travel and roller is dimensioned to make onecomplete revolution for every 8 inches of web travel. The operation ofthe electric limit switches will now be more fully described withreference to FIGURES 2 and 3.

In FIGURE 2 the worm devices 27 and 28 are shown meshing respectivelywith worm wheels 23, 3t) affording respectively gear reduction ratios of3 to l and 4 to 1. Drive shafts 31 and 32 are driven through worm wheels29 and 3t respectively and serve to actuate electric limit switches 33and 34 respectively, which comprise respectively movable contact arms 35and 36 (see FIGURE 3) each making one revolution for respectively 30inches and 32 inches of web travel, fixed contacts 37, 38 and 39 forswitch 33 and a fixed contact 4% for switch 34 governing circuits whichare completed every time 10 inches, 15 inches, 30 inches and 8 inches ofmaterial is drawn from the roll 4. In all there are six fixed contactsindicated by the reference numerals 37, 38 and 39 and four fixedcontacts indicated by the reference numeral 44 A preselector switch 41is provided readily to set the apparatus to feed predetermined lengthsof web from the roll 4, the switch 41 comprising a movable contact llaset by a manual control member 41b (FIGURE 2) readily accessible to theoperator and four fixed contacts 42, 43, 4d and 45 controlling the fourcircuits aforementioned.

As the material drawn from roll 4 passes rollers 24 and 25, they areconstantly rotated and through their associated gear drive actuate thelimit switches 33 and 34. After passing rollers 24 and 25, the web ismoved to the conveyor unit 1 through the guillotine 26, which extendsfor the full width of the machine feed path and which, as illustrated inthis figure, comprises a stationary anvil block 46 and a verticallymovable clamp bar 47 and cutting blade 4%.

The clamp bar 47 and cutting blade 48 are normally held by spring means49, slightly above the web material passing over the anvil block as, butthis movable assembly may be moved downwardly through the medium ofpressure plate 56, first to clamp the web and hold it stationary betweenanvil block 46 and clamp 4'7, continued downward movement moving blade43 to sever the web, the assembly then being returned to its normalposition by the spring means 49. Movement of the clamp and bladeassembly can be extremely rapid so that the moving web will not bebunched unduly while it is held on the anvil block.

To etfect the downward movement of the movable assembly of theguillotine, a roller 51 mounted on an arm 52 pivoted at 53, bears on thepressure plate the arm 52 being rocked about its pivot 53 by means ofarm 54 connected to the armature 55 of a solenoid generally designatedevery time the solenoid 60 is energised.

Solenoid dd is in circuit with an electro-rnagnetic contactor controlledby the aforementioned limit switches 33 and 34 and preselector switch 41so that, assuming switch ill has been set for, say 10 inches, thesolenoid will be energised every time 10 inches of material has beendrawn from the roll 4 to actuate the guillotine to ever the web into 10inch sections which are fed to the conveyor unit 1.

It will be seen, therefore, that with the guide path formed by belts l3and 14 set at a length of 30 inches, three severed sections of webmaterial each 10 inches long, will occupy the path before the firstsevered section reaches the second conveyor unit 2.

While it is preferred to slit the web longitudinally subsequent to theprinting operation, for ease of illustration, a slitting unit is shownmounted adjacent to the web feed in rollers 21 and 22, such slittingdevice being generally designated 61.

As shown in FIGURE 4, which shows a part view across the width of theslitting device, there are slitting discs 52, 63, 6d, and 66 eachmounted opposite a co-operating disc. The web passes between theslitting discs and the (so-operating discs and as shown in FIGURE 1 thelower or co-operating discs are mounted on bent arms 67 pivoted at 63and are moved by rotating cam members 69 into engagement with theslitting discs to slit the web.

The slitting discs and cooperating discs are arranged across the widthof the web, which is a 40" web, so that two of the discs will operate toslit the web into three 13.3" strips, three of the discs will slit theweb into 10" strips and one of the discs will slit the web into 20strips.

The cam members 69 are so arranged that the cooperating discs arebrought into engagement with only one of these aforesaid sets of discsat any one time. Thus there will be one set of cam members for each setof discs and co-operating discs so that the web can be slit into stripshaving the desired width.

In the case where strips 13.3 wide are produced, two double discs may beused, so designed as to remove two continuous strips each /3 wide fromthe web, so that strips of 13 web are produced.

The conveyor unit 2 comprises two sets of endless belts '70 and 71, belt7% being located by guide rollers 72, 73 and '74 with a portion of theupper run of the belts passing over a suction tank 75, while belts 71are located by guide rollers 76, '77 and 78 and arranged with its lowerrun disposed above of a portion of the upper run of belt 7 asillustrated.

To ensure the maintenance of correct relative speeds of travel betweenconveyor units 1 and 2, a chain drive is provided linking rollers 18 and19 of conveyor unit 1 with roller 72 of conveyor unit 2, a free wheeldevice being incorporated in roller '72 to prevent conveyor 1 beingdriven faster than conveyor 2 (and to permit conveyor 2 to move whenconveyor 1 is stationary).

Disposed beneath roller 76 of belts 71 and below the upper run of belts70, is a second roller 79, rollers '76 and 79 forming trap rollers, thepurposes of which will hereafter be described.

A series of trip contacts 89 are provided across the width of theendless belts iii adjacent to the aforementioned trap rollers 76 and 79,the arrangement being such that, as the severed and slit material drawnfrom the roll 4 is delivered by conveyor unit 1 to the conveyor unit 2,the material is held list on the belts 7th by means of the suction talk75, so that the belt will carry the material along with it and as thelea-ding edge of the material interrupts trip contacts 811, the webdrive motor is automatically arrested or disconnected and the sectionsof sensitised material remain stationary with their leading edges underguide member 81.

The operator now positions three master copies to be printed over thethree sections of sensitised material and either operates a manualcontrol member (not shown) to re-start the web feed mechanism or slidesthe sensitised material with superposed masters to interrupt contacts 82in series with contacts 841 to restart the web feed mechanism.

When the web feed mechanism is restarted, the sections of sensitisedmaterial, with their superposed masters, move to the trap rollers 76 and79, which impart a frictional drive thereto and feed them between belts'70 and 71 to the third conveyor unit 3 and thence around exposurecylinder 5.

Conveyor unit 3 comprises a series of endless belts 83 passing aroundroller 78, which is a sectional roller with the sections carrying belt71 rotating independently of the sections carrying belt 83 and around aconventional contact plate designated 84, belts 85 traversing thesuperposed masters and sections of sensitised material through theexposure cylinder 5.

The contact plate 84 fulfills two functions. It keeps the master sheetof sensitised material in superposed relation until they pass into thenip of exposure cylinder and serves as a roller for one end of the belt83.

A fully automatic machine embodying the invention may be constructedalso as illustrated in FIGURE 1 and as previously described, with onlyminor modifications, the arrangement being such that, instead ofproviding for intermittent movement of the web material during itspassage through the conveyor sections, the web is driven continuously.

As the web material moves continuously through the conveyor sections 1,2 and 3 detector means (e.g. photoelectric cells) are provided, suitablylocated in the feed path of the material between the belts 13 and 14, toactuate master feed mechanisms when the leading edge of a severed andslit section of web has reached the said detector means. The master feedmechanism is so arranged that by the time the said severed and slitsection of web has reached the upper run of conveyor belt 71), themasters are fed in registered and superposed relationship to the saidweb sections. In this form of the machine the guide member 81 and tripcontacts 82 are redundant.

Referring now to the machine shown in FIGURE 5 of the drawings, 101indicates a roll of sensitised material which is mounted in the machinecasing, supporting and locking arrangements being indicated by thereference numerals 102 and 103.

Any convenient mechanism may be provided for mounting and supporting theroll but as illustrated in the drawing it is mounted on a member 194which may form a portion of the machine casing pivoted at 1G5 andcarrying the supporting member 191 and locking means 1112 and 103.

The pivoted member 104 is connected by the supporting bracket 102 to awinch mechanism generally designated 106. When it is desired to mount aroll of material in the machine the winch 1% is actuated to permit themember 104 to swing about its pivot 1&5 to a horizontal or substantiallyhorizontal position resting on the ground. The roll 1111 is then movedon to the supporting bracket 162 and locked in position thereon by thelocking mechanism 163. After the leading edge of the roll has \beenthreaded into the machine the winch mechanism 106 is actuated to movethe supporting member 104 into the position illustrated in the drawing.

The machine proper comprises a pair of feed rollers 1M which may bespring pressed into engagement with each other as illustrated at 108, aguillotine device generally designated 1t19, a web slitting mechanismgenerally designated 110 and a feed path generally designated 111.

The sensitised material 112 drawn from the roll 191 after passing aroundappropriate disposed guide rollers and tracking devices diagrammaticallyshown at 113 and 114 passes into the nip of the feed rollers 107.

The feed path 111, as illustrated, comprises a pair of juxtaposedendless belts indicated at 115 and 116, the belts passing aroundappropriately disposed supporting rollers 117, 118 and 119 for the belt115 and 120 and 121 for the belt 16. Tensioning rollers 122 and 123 maybe provided as illustrated.

At the upper end of the feed path 111 adjacent to the supporting rollers119 and 121 there are provided guide fingers as indicated at 124 and 125defining a path 126 to registration rollers indicated at 127 and 128.

The exposure section of the machine is indicated generally by thereference numeral 129 and comprises a transparent cylinder 130 housing asource of actinic radiation (not shown) and a conveyor system consistingof a series of narrow endless belts 131 lapping around the cylinder 130and supported by supporting rollers 132, 133, 134, 135, 136 and 137.

It will be seen, therefore, that the sensitised material 112 drawn fromthe roll 101 may be fed along the feed path 111 to the exposure section129 of the machine.

To feed originals to be copied these are, as illustrated fed over thefeed-board 138 of the machine to a conveyor system formed by juxtaposedmoving endless belts 139 and 14%) taking around appropriately disposedrollers 141 and 142.

At the outer end of the conveyor system there is provided a second pairof guide plates 143 and 144 which also define a path 145 to theregistration rollers 127 and 128 the guide path 145 being superposed onthe guide path 126.

Along the feed path 111 there are photo-electric cells which are eachlocated at a standard sheet length from the guillotine device 1119. Theguillotine device operates when a cell located at a predetermined sheetlength detects the presence of the leading edge of a sheet of material.

A selector switch (not shown) is provided to enable the operator toselect the photoelectric cell which is to be operative during theworking of the machine (ie to select the sheet length).

As an alternative to having a series of cells along the feed path 111there may be one cell of which the position along the feed path may bevaried.

There are two further photoelectric cells located in the guide paths 126 and 145 respectively and each being the same distance away from thenip between the registration 7 rollers 127, 128. The cell in the guidepath 126 detects the leading edge of the sheet and the cell in the guidepath 145 detects the leading edge of the master to be copied.

in the operation of the machine according to this invention theoperator, as previously mentioned selects the appropriate photoelectriccell which operates the guillotine to chop the web into selected lengthsand sets the slitting wheels to slit the Webinto selected widths.

On starting the machine the feed rollers 107 are caused to rotate andthe endless belts H and 116 defining the feed path 111 commence moving.

The material 112 is thus drawn by the feed rollers from the roll ltll topass through the guillotine device Hi9 and over the slitting device 118,where the Web is slit longitudinally, and into the fed path llll.

As the leading edge of the material is detected by the photoelectriccell in the feed path the guillotine 109 is actuated transversely tosever the material 112 and the drive to the feed rollers 197 isinterrupted.

The severed and slit section of web continues to be fed along the feedpath Iii]. into the guide path 126 which leads to the registrationrollers 127 and 123 at the assembly station. When the leading edge ofthe cut section of Web is detected by the photoelectric cell in theguide path 126 the section is arrested by interrupting the drive to thefeed path 111.

An original or originals is or are then fed along the feed. path betweenthe belts 139 and lltl into the guide path 145 and when the leading edgeof the original or the leading edges of the originals is or are detectedby the photoelectric cell or cells in the guide path 145 the beltsforming the feed path 111 and the registration rollers 127, 128 are setin motion so that the cut sheets and the original or originals pass oninto the exposure section 129 in superposed relation.

An important point to mention is that the sheets and the originals arenot set in motion towards the exposure section until the leading edgesof all the items across the width of the machine are at the assemblystation.

When the registration rollers 127, 128 and the belts forming the feedpath 111 are set in motion the feed rollers lltil, 108 are also set inmotion so that the action of the machine is continuous.

Alternatively, of course, the original may have been fed to the assemblystation first or during the feed of the cut sheets of sensitisedmaterial, but in this case the photoelectric cell in the guide path 145will stop the movement of the belts 139, 140 until the slit sheets aredetected at their assembly point.

Thus it does not matter whether the slit sheets or the masters arrivefirst at the assembly station. The machine will not feed into theexposure section until both sets of photoelectric cells have detectedthe presence of their respective sheets or masters.

Thus it will be appreciated that the action of the two photoelectriccells, one in each of the guide paths 126 and 145 respectively, are sointerconnected that the first of the cells to be sensitised by thearrival of a master or a sheet (dependent on which arrives first) actsto stop the feed of the article which it has detected, while the secondcell on being sensitised acts to set the sheet and the master in motionthrough the registration rollers 127, 128 and the exposure section 129.

While reference has been made to the use of juxtaposed endless movingbelts to provide the feed paths for the originals and sensitisedmaterials it is to be understood that this is given merely as'an exampleand that any other sheet transport devices may be employed such as forinstance roller systems employing driven and idler rollers.

i claim:

1. A photocopying apparatus consisting of:

(a) at an exposure station means for exposing sensitized material ([1)means for progressively feeding a web of sensitized material to acutting station (c) cutting means at the cutting station operable to cutthe web transversely (cl) control means which operates the cutting meanseach time a predetermined length of the web has passed the cuttingstation whereby to produce a succession of sheets each of apredetermined length (2) means to feed the cut sheets in succession toan assembly station detection means to detect the arrival of the leadingedge of a cut sheet at the assembly station (g) means responsive to thedetection of the arrival of the leading edge of a sheet by the detectionmeans to stop the "feeding means for the sheet (It) means at theassembly station whereby the cut sheets and masters to be copied may besuperposed on one another and (i) means for feeding the superposedsheets and masters through the exposure station.

2. A photocopying apparatus as claimed in claim 1 and including at theassembly station master detection means for etecting the presence at theassembly station of a master to be copied, and means responsive to thedetection, of a sheet and of a-master as aforesaid to assemble and feedthe sheet and the master in superposed relation through the assemblystation.

3. A photocopying apparatus as claimed in claim 1 in which the mastersare superposed manually on the cut sheets and there is manually operablecontrol means to operate the means to feed the superposed sheets andmasters through the assembly station.

4. Apparatus as claimed in claim 1 in which between the cutting stationand the assembly station there is a feed path for the cut sheets, whichfeed path has a length at least equal to the predetermined length of acut sheet.

5. Apparatus as claimed in claim 4 in which the length of the said feedpath is equal to the total length of an integral number of cut sheetsand the cutting means is actuated by its control means when the feedingmeans for the cut sheets is inoperative.

6. Apparatus as claimed in claim 5 in which the control means and thelength of said feed path are adjustable to vary the said predeterminedlength of the cut sheets.

References Cited by the Examiner UNITED STATES PATENTS 2,732,778 1/56Limberger 77.5 3,044,386 7/62 Limberger 95-775 3,076,400 2/63 Lirnberger95-75 EVON C. BLUNK, Primary Examiner.

JOHN M. HORAN, Examiner.

1. A PHOTOCOPYING APPARATUS COMPRISING OF: (A) AT AN EXPOSURE STATIONMEANS FOR EXPOSING SENSITIZED MATERIAL (B) MEANS FOR PROGRESSIVELYFEEDING A WEB OF SENSITIZED MATERIAL TO A CUTTING STATION (C) CUTTINGMEANS AT THE CUTTING STATION OPERABLE TO CUT THE WEB TRANSVERSELY (D)CONTROL MEANS WHICH OPERATES THE CUTTING MEANS EACH TIME A PREDETERMINEDLENGTH OF THE WEB HAS PASSED THE CUTTING STATION WHEREBY TO PRODUCE ASUCCESSION OF SHEETS EACH OF A PREDETERMINED LENGTH (E) MEANS TO FEEDTHE CUT SHEETS IN SUCCESSION TO AN ASSEMBLY STATION (F) DETECTION MEANSTO DETECT THE ARRIVAL OF THE LEADING EDGE OF A CUT SHEET AT THE ASSEMBLYSTATION (G) MEANS RESPONSIVE TO THE DETECTION OF THE ARRIVAL OF THELEADING EDGE OF A SHEET BY THE DETECTION MEANS TO STOP THE FEEDING MEANSFOR THE SHEET (H) MEANS AT THE ASSEMBLY STATION WHEREBY THE CUT SHEESAND MASTERS TO BE COPIED MAY BE SUPERPOSED ON ONE ANOTHER AND (I) MEANSFOR FEEDING THE SUPERPOSED SHEETS ADN MASTERS THROUGH THE EXPOSURESTATION.